1. Field of the Invention
The present invention relates to an electric oven, and more particularly, to a heater cooling structure that can intensively cool only a seal portion of a halogen heater using the heat conduction.
2. Description of the Related Art
An electric oven is generally used for baking or roasting food by heating the food using heat and steam generated from the food and confined in the oven. Therefore, the food can be cooked with a good taste without being burnt or hardened by contraction, which caused when the food is directly roasted by fire.
A typical electric oven includes a cavity in which food is loaded and a door for opening and closing the oven to load and withdraw the food in and from the cavity. A heat source such as a heater is placed in the cavity.
The heater includes an upper infrared heater mounted on an upper portion of the cavity, a lower heater mounted on a lower portion of the cavity to increase an operation temperature of the cavity and a convection heater mounted on a rear portion of the cavity to bake the food. A fan is provided around the convection heater to circulate fluid in the cavity.
The electric oven heats the food by transferring thermal energy to the food by turning on one or more of the upper, lower and convection heaters or by alternately turning on them.
When the heater is a sealed quartz tube heater such as the halogen heater, the seal portion to which a lead wire is connected is formed by compressing the glass. When a temperature of the seal portion increases to a predetermined level (about 250° C., a gap is created due to the thermal expansion between the metal and glass and thus air may be introduced into the quartz tube through the gap, thereby reducing the service life of an inner filament of the quartz tube.
To solve the problem, a cover is provided with a plurality of holes to cool the seal portion.
However, although the forming of the holes on the cover may have an advantage of cooling the seal portion, thermal energy may leak through a gap created by a structure of the heater, a reflection plate or the like. Due to this, the temperature of the electric component room may increase, thereby deteriorating the food heating efficiency.